The invention relates to an apparatus for the insertion and/or removal of a mask for a preferably flat, circular substrate through the airlock of the chamber of a vacuum coating apparatus with a plunger displaceably mounted in a first airlock chamber and movable into the plane of the substrate, for the mounting and for the transport of the mask provided with a receiving bore.
It is known to partially cover disk-like substrates, such as CD-ROMs or magneto-optical discs, with templates or to provide them with masks before coating them in vacuum coating apparatus, so that the marginal zones or central portions of the substrates will remain free of a coating. Such cover templets or masks are usually applied to the substrates before the coating process, i.e., outside of the vacuum area, so that the substrates together with the masks fastened to them can enter the processing chamber of the coating apparatus through an airlock or leave it through the airlock after the coating process. This kind of masking has the disadvantage that the masks are rapidly "used up," since incrustation forms their external surfaces, which can considerably interfere with the coating process.